** ** what is the length of the altitude of the equilateral triangle below?

For any 30-60-90 triangle:
Let the length of hypotenuse = x
∴ The leg which faces the angle 30 = (1/2) x 
And the leg which faces the angle 60 = (√3/2) x 
So, The ratio between two legs will be 
= (1/2) x : (√3/2) x     ⇒⇒⇒⇒ divide over x
= 1/2  :  √3/2             ⇒⇒⇒⇒ multiply by 2
= 1  :  √3

Or the ratio will be

= (√3/2) x  :  (1/2) x    ⇒⇒⇒⇒ divide over x
= √3/2  :  1/2             ⇒⇒⇒⇒ multiply by 2
=  √3  :  1


The correct answer will be option B only

B.  1 : √3